Boat coupling

ABSTRACT

A boat coupling including a jaw for receiving an eye which is attached to the hull of a boat. A pin is movable to bridge across the jaw to capture the eye between extended and retracted positions. A retaining arrangement for retaining the pin in the retracted position will release the pin upon the pin being shifted to a release position, where after the pin is moveable under a biasing influence to shift to the extended position

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/140,620, filed on Jun. 17, 2011, which application is a nationalphase entry under 35 USC §371 of International Application No.PCT/AU2009/001650, filed Dec. 18, 2009, which claims the benefit ofAustralian Patent Application No. 2008906513, filed Dec. 18, 2008. Theentire disclosures of each of the above-identified applications areincorporated by reference herein.

FIELD OF THE INVENTION

The present invention relates to a boat coupling for securing the hullof a boat, typically small to medium size pleasure and commercial boats,to a trailer.

BACKGROUND OF THE INVENTION

Small to medium size pleasure and commercial boats are often towed bycar or truck on a boat trailer to a launch site or ramp. The boat isnormally secured to the trailer by a winch and cable arrangement whichengages an eye which is attached to the boat hull, most often at the bowor middle bow section of the hull. Various couplings have been devisedfor securing a boat to a trailer, however typically these are of complexconstruction and/or require an operator to operate the coupling at or inthe immediate vicinity of the coupling and this can mean that when aboat is being launched into or removed from the water, the operator mustenter the water to connect or disconnect the coupling between the boatand the trailer. This is inconvenient and usually leaves at least thefeet and lower legs of the operator wet. Also, it usually means thatduring launching of a boat into the water, two persons are required, oneto operate the boat and the other to release the coupling.

Various attempts have been made to relieve the need for the couplingoperator to be positioned at or in the immediate vicinity of thecoupling, when latching or releasing of the boat relative to the traileris undertaken. U.S. Pat. No. 3,963,263 discloses an automatic boattrailer latch which includes two pivotable strikers that are engaged byan eye attached to the boat hull during attachment of the boat to thetrailer and which pivot to create an opening through which the eye canpass. Once the eye is past the strikers, the strikers can return underthe influence of springs, to a position in which release of the eye pastthe strikers is prevented by the strikers. Thus, the eye is captured bythe strikers and the boat is secured to the trailer. To release the eyefrom the strikers, the strikers are manually rotated to create theopening mentioned above, to allow passage of the eye past the strikers.While the latch arrangement of U.S. Pat. No. 3,963,263 can securelycapture the eye, the arrangement has several disadvantages. Onedisadvantage is that the boat operator is required to very preciselymanoeuvre the boat to align the eye for passage past the strikers. Thereis because the latch has a very small point of entry so that there isvery little tolerance for misalignment. This is very difficult inpractice because boats move around considerably on the water during boatretrieval and boat launch angles vary considerably. Accordingly, itwould be expected that the latch of this patent would result in manyfailed retrieval attempts.

In addition, in the captured condition of the eye within the latch, theeye is in contact with the structure of the latch and this will imposeloads on the eye when the boat is being trailed, which will transfer tothe boat hull. Moreover, the latch has exposed springs which can bedangerous, the overall construction appears to less robust thandesirable, and there is not a simple release arrangement for release ofthe eye.

U.S. Pat. No. 5,193,835 discloses another form of automatic boat trailerlatch which includes a spring loaded locking pin which has retracted andextended positions and which is engaged by a spring loaded blocking pinin the retracted position, to prevent the locking pin from moving to theextended position. The blocking pin is connected to a trigger which isengaged by the eye of a boat when the boat is moved onto a trailer andmovement of the trigger causes the blocking pin to be shifted out ofengagement with the locking pin. This releases the locking pin to theextended position through the eye, so securing the boat to the trailer.A drawback with this arrangement is the complex fabricated constructionwhich is labour intensive to manufacture and not conducive to massproduction. This arrangement also suffers from having a very small pointof entry, so that it will be difficult to align the eye attached to thehull for entry into the latch. Because of this, the eye is likely toengage the latch housing during a retrieval operation and cause thehousing to bend or break. Also, there is not a simple releasearrangement for release of the eye.

In general, the couplings known to the applicant for the purposediscussed above are either of poor design and therefore costly andsubject to a greater likelihood of failure, or are simple and lessuseful. Accordingly, the applicant considers it desirable to provide aboat coupling that is of relatively simple and robust construction, thatis reliable and able to withstand heavy impacts that occur from time totime. The applicant also considers it desirable to provide a boatcoupling that is operable remotely, so that the driver or an occupant ofa vehicle to which the boat trailer is attached, or the driver or anoccupant of the boat, can operate the coupling from within the vehicleor boat, preferably without having to shift either from the driver'sseat of the vehicle or from the driver's position in the boat. Theability for the boat driver to release the boat remotely is particularlyuseful, given that the launch of a boat can then be a single personoperation rather than requiring at least two persons.

SUMMARY OF THE INVENTION

The present invention provides a boat coupling which includes:

-   -   i a jaw for receiving an eye which is attached to the hull of a        boat,    -   ii a pin which is movable between an extended position in which        it bridges across the jaw to capture the eye and a retracted        position in which the jaw is open for release of the eye,    -   iii a retaining arrangement for retaining the pin in the        retracted position, the retaining arrangement releasing the pin        upon the pin being shifted to a release position whereafter the        pin shifts to the extended position.

The jaw can take any suitable form such as a V or U shaped form.Typically, the eye which is attached to the boat hull will form a closedloop and the jaw will define an opening of sufficient depth and width toreceive the eye and for the pin to extend through the loop in theextended pin position. The jaw can be shaped to guide the eye into theopening such as by inclined and mutually converging surfaces, againstwhich the eye can slide. It will be appreciated that insertion of theeye into the jaw opening relies on correct positioning of the boatrelative to the boat coupling and this can be difficult, particularly inrough conditions. Accordingly, the provision of guide surfaces can behighly advantageous.

The jaw can be formed from any suitable metal, such as iron oraluminium, or from suitable plastic. The jaw can be cast or fabricated.

The pin can be of any suitable shape. An elongate pin can be employed ofany suitable cross-section, such as circular. Square, hexagonal or othernon-circular cross-sectional shapes can be employed if required.

The pin can be formed from any suitable metal, such steel or brass, oreven plastic.

The pin can be located within a bore formed in a housing. The jaw can beformed as part of the housing. The housing and the jaw can be integrallyformed, such as in a single casting.

The pin can be movable along its lengthwise axis between the retractedposition and the extended position. The pin can be guided within thebore for that movement. The axis of the pin is envisaged to be orientedsubstantially horizontally when the boat coupling is installed.

The pin can be shifted from the retracted position to the releaseposition against the influence of a biasing arrangement. Thus, thebiasing arrangement is operable to resist inadvertent movement of thepin to the release position from the retracted position and thus resistinadvertent release of the pin for movement to the extended position.The pin can also be shifted from the release position to the extendedposition under the influence of a biasing arrangement and to move to theretracted position against the influence of that biasing arrangement.

The boat coupling can include a retracting arrangement for retractingthe pin to the retracted position. In absence of a retractingarrangement, the pin can be retracted by pushing the pin with a suitabletool, or even by finger pressure. However if a retracting arrangement isprovided, the arrangement can include a drive member for engaging thepin and for driving the pin from the extended position to the retractedposition. The drive member can be rotatable to drive the pin in thismanner. The drive member can be connected to an actuator to drive thedrive member to rotate. The actuator can be an arm. The advantage ofthis arrangement is that the arm can be of a length suitable to reducethe effort required to shift the pin to the retracted position. Thedrive member can be positioned within the housing with the actuatorextending outside the housing for manual access.

The drive member can engage the pin in the retracted position to retainthe pin in that position. The drive member can include an engagementportion for engaging the pin, with one of the engagement portion and thepin having a recess and the other having a protrusion. In the engagedcondition of the drive member and the pin, the protrusion extends intothe recess. This arrangement can be such that with the engagementportion engaged with the pin, the drive member and the pin jam, thuspreventing the pin from moving from the retracted position in adirection towards the extended position. Where the drive member isrotatable, this arrangement jams the drive member against rotation in adirection that would drive the pin towards the extended position.

In the above arrangement, movement of the pin from the retractedposition to the release position causes the protrusion to be displacedfrom the recess so that the drive member and the pin are no longerjammed together. Following this, the pin can be driven by the drivemember from the retracted position to the extended position.

The protrusion can be formed by a free end portion of a wall of a recesswhich is formed in the pin. The recess can be formed at the trailing endof the pin.

The drive member can be biased to rotate in a direction to drive the pintoward the extended position and the drive member can be coupled to thepin so that upon the pin being shifted to the release position, thedrive member then drives the pin to the extended position.Advantageously, the arrangement can be such that rotational movement ofthe drive member can cause linear movement of the pin. The drive membercan be arranged to shift the pin in either direction between theretracted position and the extended position. Alternatively, a seconddrive member can drive the pin towards the retracted position from theextended position.

In some arrangements, the pin can include a recess and the drive membercan engage within the recess to drive the pin between the extendedposition and the retracted position. The drive member can engage a firstsurface of the recess to drive the pin towards the extended position anda second surface of the recess to drive the pin towards the retractedposition. The first and second surfaces can be spaced apart along theaxis of the pin and can be opposed or facing surfaces.

Other mating recess and protrusion arrangements are possible and withinthe scope of the invention, as are other drive arrangements to drive thepin between the retracted and extended positions.

For a better understanding of the invention and to show how it may beperformed, embodiments thereof will now be described, by way ofnon-limiting example only, with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a boat coupling according to the invention engaged with aneye.

FIG. 2 is a side view of the boat coupling of FIG. 1, with the pinretracted and the eye displaced.

FIG. 3 is a view of the boat coupling of FIG. 2, rotated through 90°.

FIG. 4 is a side view of the boat coupling of FIG. 1, with the pinextended and the eye displaced.

FIGS. 5 to 7 show the sequence of movement of the pin from the retractedposition to the extended position.

FIGS. 8 and 9 show the boat coupling of FIG. 1 attached to a boat.

DETAILED DESCRIPTION OF THE FIGURES

FIG. 1 shows a boat coupling 10 according to one embodiment of theinvention. The boat coupling 10 is shown in FIG. 1 as being coupled toan eye 11, which normally would be fixed to the hull of a boat (notshown). The eye 11 forms a closed loop 12 and includes three openings 13along a portion 14 thereof through which fastening bolts or screws canextend for fastening the eye 11 to the boat hull.

The boat coupling 10 would be fitted to a mount on a boat trailer andincludes a jaw 15 which is formed in a U-shape, defining a pair of jawarms 16 and a base 17. The jaw 15 defines an opening 18 which issufficient in width and depth, to accept the eye 11 in a position toenable the pin 20 of the coupling 10 to extend through the loop 12.

FIG. 2 shows the coupling 10 in plan view and shows the eye 11 spacedfrom the jaw 15 of the coupling 10. FIG. 2 also shows the pin 20 in aretracted position, which allows insertion of the eye 11 into theopening 18 of the jaw 15 to the position shown in FIG. 1. In theposition of FIG. 2, the pin 20 can be extended to capture the eye 11within the jaw 15. The inside surfaces of the jaw arms 16 are inclinedfor guiding the eye 11 into the opening 18.

FIG. 3 is a view of the coupling 10, but shown rotated through 90° fromthe FIG. 2 orientation. In FIG. 3, the pin 20 remains in the retractedposition shown in FIG. 2.

FIG. 4 is a similar view to that shown in FIG. 2, except that the pin 20is shown in an extended position. Additionally, an end cap 25 of thecoupling 10 is shown separated from the housing 26 of the coupling 10.

The pin 20 of the figures is an elongate rod of generally circularcross-section. The leading end 27 of the pin 20 is tapered or conical(see FIGS. 1 to 3), while the other end is obscured in FIGS. 1 to 4 andwill be described later herein in relation to FIGS. 5 to 7.

The coupling 10 includes a mounting plate 30, which is provided formounting the coupling 10 to a boat trailer or the like. The mountingplate 30 simply includes four openings for the passage of fasteningbolts to fasten the boat coupling 10 to a mount of a trailer.

The coupling 10 includes a retracting arrangement for retracting the pin20 from the extended position shown in FIGS. 1 and 4, to the retractedposition shown in FIGS. 2 and 3. The retracting arrangement includes anactuating arm 31 which is rotatable through an arc shown by the arrow Ain FIG. 2. Rotation is about an axis which extends perpendicular to thelengthwise axis of the pin 20. This is best illustrated in FIG. 1, inwhich the arm 31 is shown as having three sections 32 to 34 with theaxis of rotation being about the axis of the section 34. The sections 32and 33 are angled relative to each other, although the angle can varydepending on the application of the coupling 10 and in fact no anglebetween these sections need necessarily be provided. Thus, in analternative arrangement, the sections 32 and 33 can extend along thesame axis.

A bias spring 40 is anchored to the housing 26 at a projection 41 and tothe arm section 33, by engagement in an opening 42 formed in thatsection. By anchoring the spring 40 at the projection 41 and the opening42, the arm 31 can be biased towards anti-clockwise movement when viewedin the orientation shown in FIG. 2. As will be explained below, biasingof the arm 31 in that direction is such as to drive the pin 20 to theextended position, when the pin 20 is released for movement to thatposition.

By linking or connecting the arm 31 to the pin 20, through a linking orconnecting arrangement disposed within the housing 26, upon the pin 20being released from the retracted position shown in FIG. 2, the biasinginfluence which is applied to the arm 31 by the spring 40, can be usedto cause the pin 20 to move quickly, or abruptly, to the extendedposition shown in FIGS. 1 and 4. The pin can therefore be arranged tosnap into the extended position as soon as the eye enters the opening 18of the jaw 15.

Moreover, the entry of the eye into a position between the jaw arms 16can be employed to shift the pin 20 to the release position, tothereafter move to the extended position. This provides for a verysimple coupling construction with minimum components and is discussed indetail below, in relation to FIGS. 5 to 7.

With reference to the sequence of movement shown in FIGS. 5 to 7, thepin 20 and a drive member 45 are illustrated. The drive member 45 formspart of a retracting and driving arrangement, of which the actuating arm31 also forms a part. For the description of FIGS. 5 to 7, it should beunderstood that the actuating arm 31 is connected to the drive member 45by connection of the arm section 34 to the distal end 46 of the member45. The section 34 is rigidly connected to the member 45, so thatrotation of the arm 31 causes rotation of the member 45. That connectioncan be a threaded connection, or it can be by welding or by configuringthe cross-section of the arm section 34 to be non circular and fittinginto a non circular opening in the member 45.

The pin 20 is elongate and is closely mounted within a bore 47 withinthe housing 26. By this arrangement, the pin 20 is constrained tomovement along its lengthwise axis.

In FIG. 5, the pin is shown in the retracted position, in which theleading end 27 only just extends out of the bore 47. This smallextension out of the bore 47 is deliberate, as movement of the pin 20 tothe release position is dependent on the leading end 27 being engaged bythe eye 11 and as a result of that engagement, the pin 20 being shifteda small distance in the direction D2 (FIG. 6) into the bore 47.

The spring 53 of FIG. 5 (see FIG. 4 also) biases the pin 20 in thedirection D1, but that biasing influence is only light and is exerted onthe pin 20 when the pin 20 is at or close to the retracted positionshown in FIG. 5. The spring 53 operates to maintain the connectionbetween the arm 45 and the pin 20 (noting that the arm 45 is biasedclockwise in FIG. 5 by the actuating arm 31 on which the spring 40acts), so that that connection is not disengaged through vibration, suchas when a boat is being trailed by a vehicle.

The spring 53 is connected to the end cap 25, which removably closes theopen end of the housing 26.

In FIG. 5, the pin 20 and the arm 45 are connected by engagement betweenthe end wall 51 of the recess 50 within the recess 52 formed at thedistal end of the arm 45. The arrangement is such that the arm 45 is notable to rotate while the end wall 51 is engaged within the recess 52because the arm 45 is effectively jammed with the pin 20. This isbecause for the arm 45 to rotate anti-clockwise, the pin has to shiftlaterally, but it is restrained against that movement by its locationwithin the bore 47. Because the arm 45 cannot rotate, the pin 20 cannotbe driven toward the extended position of FIG. 7. The pin 20 is thuseffectively restrained against movement in the direction D1.Accordingly, for the pin 20 to move to the extended position, theconnection between the end wall 51 and the recess 52 must bedisconnected which will thereafter permit the arm 45 to rotateanti-clockwise. This is achieved as follows.

With the pin 20 retained in the retracted position shown in FIG. 5, theeye 11 can be introduced into the jaw 15, between the jaw arms 16.However, the gap G shown in FIG. 5 is not sufficient to allow the eye 11to pass into the opening 18 of the jaw 15 without the eye 11 engagingthe leading end 27 of the pin 20. The eye 11 thus engages the leadingend 27 against the side surface 54 and causes the pin 20 to be pushedslightly into the bore 47 of the housing 26. The pin 20 is thus shiftedby that engagement to the release position.

The movement of the pin 20 described above causes the pin 20 to moverelative to the arm 45 against the bias of the spring 53, because thearm 45 is not able to rotate clockwise any further than that shown inFIG. 5. This constraint of the arm 45 against further rotation can beachieved in any suitable manner such as by a suitable stop 56 that thearm 45 engages at the maximum point of rotation or simply by theanti-clockwise bias load imposed on the arm 45 by the spring 40.

Movement of the pin 20 relative to the arm 45 causes disconnection ofthe end wall 51 from the recess 52 as shown in FIG. 6. Following thatdisconnection, the arm 45 can rotate anti-clockwise under the biasinginfluence of the spring 40 and because the pin 20 is no longerrestrained against movement in the direction D1, the arm 45 can drivethe pin 20 to the extended position shown in FIG. 7 as follows. Once theend wall 51 has been disconnected from the recess 52, the distal end ofthe arm 45 can move into the recess 50 to allow full rotation of the arm45. The arm 45 drives the pin 20 by engagement with the recess surface57, rolling on that surface as the pin 20 moves in the direction D1.

Movement of the pin 20 from the release position shown in FIG. 6 to theextended position shown in FIG. 7 can be extremely quick depending onthe biasing load applied by the spring 40 to the actuating arm 31 andthus to the drive arm 45. Extremely quick movement is preferred, so thatthe eye 11 is captured almost as soon as it enters the jaw 15.

By the arrangement discussed above, the eye 11 has been captured in thejaw 15, so that the boat to which the eye 11 is attached is secured tothe trailer to which the boat coupling 10 is attached.

When the eye 11 is to be released from the jaw 15 for launching a boatfrom a trailer, the actuating arm 31 is rotated clockwise to rotate thedrive arm 45 clockwise, in order to drive the pin 20 in the direction D2until the eye 11 can clear the pin 20 and withdraw from the jaw 15. Thedrive member 45 will drive against the surface 58 of the recess 50 asshown in FIG. 7 to push the pin 20 into the bore 47 in the direction D2.Rotation of the actuating arm 31 clockwise is against the biasinginfluence of the spring 40.

Once the eye 11 has withdrawn from the jaw 15, the pin 20 can return tothe extended position of FIG. 7 or can be reset to the retractedposition of FIG. 5. It is to be noted that if the pin 20 is driven tothe retracted position of FIG. 5 to allow withdrawal of the eye 11 fromthe jaw 15, the eye 11 will engage the leading end 27 of the pin 20during movement out of the jaw 15, which will push the pin 20 to therelease position. This will allow the pin to return to the extendedposition after the eye 11 has cleared the jaw 15 unless the operatorreturns the pin 20 to the retracted position by rotation of the arm 31.

When it is time to remount the boat on the trailer, the pin is driven tothe retracted position by rotation of the arm 31 and the boat can bedriven to a position in which the eye 11 is aligned for insertion to thejaw 15. As the eye 11 enters the jaw 15, it will engage the side surface54 of the leading end 27 of the pin 20, causing the pin 20 to move inthe direction D2 (FIG. 6), and releasing the retaining connectionbetween the end wall 51 and the recess 52 as described earlier. Withthat connection released, the pin 20 can be driven by the drive member45 to the extended position of FIG. 7 and the eye 11 and therefore theboat to which the eye 11 is attached, is again secured to the coupling10.

Advantageously, the boat coupling 10 can be arranged to provide anaudible click when the pin 20 has reached either or both of theretracted and extended positions. In the retracted position, the audibleclick can occur when the end wall 51 is received within the recess 52.That indicates to the operator that the retracted position of the pin 20has been reached and the arm 31 can be released. In the extendedposition, the leading end 27 of the pin 20 can engage in an opening 59in the jaw 15 to create the audible click so that the boat driverreceives an audible indication that the eye 11 is properly secured tothe coupling 10. Other arrangements to produce an audible click arewithin the scope of the invention.

FIGS. 8 and 9 illustrate the bow 60 of a boat 61 which is secured by thecoupling 10 to a trailer 62. The trailer 62 includes the normal winch62, which can be secured to an eye 64, and rollers 65 or a V-block,which engage either side of the bow 60. The coupling 10 is secured to amember 66, which is secured to a trailer bow post 67.

A ring 55 (see also FIGS. 1 to 4) is secured to the end of the arm 31and a flexible cord or rope 68 is secured to the ring 55 via a clip 69.The rope 68 extends towards the rear of the boat for access by the boatdriver 70, whereby a pull on the rope 68 rotates the arm 31 to releasethe pin 20 from the eye 11, so that the boat can slip or be driven offthe trailer 62. Thus, it will be apparent that the coupling 10 can beremotely operated so that the boat driver can remain in the drivingposition to release the boat from the trailer 62. The rope could equallyextend to the driver of the car which is towing the trailer, or even toa bystander for remote operation.

The boat coupling 10 provides significant operating advantages, and inparticular, it enables the boat driver to release the eye 11 from thecoupling 10 from a position within the boat. That is, the operator doesnot need to be actually at the coupling 10. Thus, a boat which istrailed to a launch site with the pin in the extended position shown inFIG. 7, capturing the eye 11 within the jaw 15, can be released from thetrailer by retracting the pin 20 remotely by pulling on the arm 31through the rope 68 to withdraw the pin 20 to the retracted position ofFIG. 5. The boat can then be reversed off the trailer in the usualmanner.

The coupling 10 has minimum component parts but is robust and isexpected to be relatively maintenance free and importantly, requires nolubrication. Each of the housing 26 of the coupling 10, the pin 20 andthe drive member 45 can be cast without further significant machining,thus minimising the cost of production. The coupling 10 is compact andtherefore is easy to fit into the restricted area at the bow region ofthe trailer (see FIG. 8). The coupling 10 eliminates the need for asafety chain as a secondary safety device to the winch. Advantageously,the eye is not generally in contact with the coupling so that there isgenerally no wear of the coupling during trailing of a boat and there isgenerally no loading applied to the boat through the eye duringtrailing. A particular advantage is that the coupling 10 can be operatedfrom positions within a boat or a car or truck, so that there is no needto be actually at the coupling for its operation. Other latching deviceshave to be set or switched for launch when the boat is nearly in thewater, because those latching devices are not sufficiently secure forholding a boat to a trailer even for short distances. With the coupling10, the winch can be disconnected from the boat well away from the waterbecause the coupling will hold the boat securely for the remainingdistance to the water. The trailer can be driven straight into the waterand the coupling released by the boat driver without either the boat orvehicle driver having to move from their driving positions.

The invention described herein is susceptible to variations,modifications and/or additions other than those specifically describedand it is to be understood that the invention includes all suchvariations, modifications and/or additions which fall within the spiritand scope of the above description.

Future patent applications may be filed in Australia or overseas on thebasis of or claiming priority from the present application. It is to beunderstood that the following provisional claims are provided by way ofexample only, and are not intended to limit the scope of what may beclaimed in any such future applications. Features may be added to oromitted from the provisional claims at a later date so as to furtherdefine or re-define the invention or inventions.

The claims defining the invention are as follows:
 1. A boat couplingincluding: a jaw for receiving an eye which is attached to the hull of aboat; a pin which is movable between an extended position in which itbridges across the jaw to capture the eye and a retracted position inwhich the jaw is open for release of the eye; and a retainingarrangement for retaining the pin in the retracted position, theretaining arrangement releasing the pin upon the pin being shifted to arelease position whereafter the pin is movable under a biasing influenceto shift to the extended position; wherein the jaw defines an openinginto which the eye is received for capture by the pin and in theretracted position of the pin, a leading end of the pin extends into theopening and presents a surface for engagement by the eye as the eyeenters the opening, the surface being shaped so that upon engagement bythe eye, the pin is shifted to the release position.
 2. A boat couplingaccording to claim 1, the pin being elongate and defining a lengthwiseaxis, the pin being movable between the retracted position and theextended position along the lengthwise axis, wherein the pin is shiftedto the release position from the retracted position along the lengthwiseaxis thereof in a direction opposite to the direction of movement of thepin from the retracted position to the extended position.
 3. A boatcoupling according to claim 2, wherein the pin is shifted to the releaseposition against the influence of a bias arrangement.
 4. A boat couplingaccording to claim 1, further including a retracting arrangement forretracting the pin to the retracted position, the retracting arrangementincluding a drive member for engaging the pin and for driving the pinfrom the extended position to the retracted position.
 5. A boat couplingaccording to claim 4, the drive member being rotatable about an axiswhich extends perpendicular to the lengthwise axis of the pin to drivethe pin from the extended position to the retracted position.
 6. A boatcoupling according to claim 5, the drive member being connected to anactuator to drive the drive member to rotate.
 7. A boat couplingaccording to claim 6, the actuator being formed as an arm.
 8. A boatcoupling according to claim 4, the drive member forming part of theretaining arrangement and the drive member engaging the pin in theretracted position to retain the pin in the retracted position.
 9. Aboat coupling according to claim 4, wherein the drive member is biasedto rotate in a direction to drive the pin toward the extended positionand the drive member is coupled to the pin so that upon the pin beingshifted to the release position, the drive member drives the pin to theextended position.
 10. A boat coupling according to claim 1, wherein inuse the axis of the pin is substantially horizontal.
 11. A boat trailerincluding a boat coupling according to claim
 1. 12. A boat couplingaccording to claim 1, the leading end of the pin presenting an inclinedsurface for engagement by the eye.
 13. A boat coupling according toclaim 1, the leading end of the pin presenting a conical surface forengagement by the eye.
 14. A boat coupling according to claim 6, theactuator being rotatable about the axis of the drive member.
 15. A boatcoupling according to claim 8, the pin and the drive member being jammedtogether in the retracted position of the pin and being released fromjamming upon the pin being shifted to the release position.
 16. A boatcoupling according to claim 5, the drive member forming part of theretaining arrangement and the drive member engaging the pin in theretracted position to retain the pin in the retracted position, the pinand the drive member being jammed together in the retracted position ofthe pin whereby the drive member is jammed against rotation and thedrive member being released from being jammed against rotation upon thepin being shifted to the release position whereafter the drive member isrotatable under a biasing influence to drive the pin towards theextended position.